Different spraying, blowing devices, as e.g. dyestuff spraying guns, mortar throwers, sand blasting apparatuses, are widely used in the industry. The guns and apparatuses, resp. developed for the most diverse purposes meet more ar less the requirements. However, the known apparatuses have also well-known disadvantageous features. So, e.g. in the case fo dye sprayer operated with air-atomization, only highly diluted dyestuffs can be used. Although airless spraying guns are suitable for thicker dyestuffs, a special quality of dyestuff is nedded, and a they work at an overpressure of 120 to 160 which is disadvantageous from several point of view.
It is characteristic of all the known spraying guns that spraying is possible in the direction of the longitudinal axis, i.e. straight forward only. However, in practice one is often confronted with the task to coat the "backside" of pipes, cables, frameworks, etc. which are convered or concealed by a wall, i.e. surfaces ought to be coated which cannot be seen. This work is presently performed manually, using bent brushes. The drawback of this forcible solution lies in that partly manual work is expensive and unreliable, in addition to this live labour does not stay always available, in spite of high wages. A further disadvantage lies in the fact that there are coating materials, e.g. different slurries and dispersions, which cannot be applied on surfaces in the desired quality by using a brush.
The majority of the known spraying devices are discontinuously operated, accordingly automatic, continuous operation is not possible or one has to overcome considerable difficulties in this respect.
No spraying gun has become known up to now which would be equally suitable for spraying or blasting diluted and thick dyestuff, slurries containing rough particles or just dry particles, as e.g. corundum flasting onto the surfaces to be coated or cleaned.